A Novel Conical Active Magnetic Bearing With Claw Structure

Generally, both radial magnetic bearing stators and combination (radial and thrust) magnetic bearing stators are distributed in radial space. Besides, most magnetic bearings operate with additional thrust disk on the rotor. These magnetic bearing structures are not applicable in the case when radial dimension is limited due to their large radial construction sizes. A novel claw active magnetic bearing (CAMB) with smaller radial construction size is proposed in this paper. This magnetic bearing has a claw-like structure, and both the stator core and coils are located along axial direction, thus it has a small radial extension, which is almost the same as the rotor diameter. The proposed magnetic bearing is suitable for use in the case when radial space is limited. Initially, the structure and working principle of the CAMB are demonstrated. Then, the analytical formulas for calculating the magnetic force of this bearing are deduced using the magnetic circuit method and the virtual displacement principle. Finally, a 3-D finite element model of the CAMB is built, and then the magnetic field distribution under different conditions and basic force characteristics of this magnetic bearing are analyzed by 3-D finite element method.